CN113412160A

CN113412160A - Connection structure

Info

Publication number: CN113412160A
Application number: CN201980091573.0A
Authority: CN
Inventors: S·库恩特
Original assignee: Eppendorf SE
Current assignee: Epedov Europe Ag
Priority date: 2018-12-18
Filing date: 2019-12-16
Publication date: 2021-09-17
Also published as: JP7270043B2; EP3669992A1; WO2020127121A1; JP2022514749A; US20220040709A1

Abstract

The invention relates to a connection arrangement (100) between a drive shaft (104) and a centrifuge rotor (102) of a laboratory centrifuge (200), which connection arrangement (100) allows one-handed operation without any additional tools. The connecting structure (100) is designed such that the locking mechanism (118, 132, 134) is always ensured, thereby preventing jamming or blocking of the locking element (118, 134).

Description

Connection structure

Technical Field

The present invention relates to a connection between a centrifuge rotor and a drive shaft of a centrifuge motor according to the general concept of claim 1.

Background

Centrifuge rotors are used in centrifuges, in particular laboratory centrifuges, to separate components of a sample centrifuged therein by using mass inertia. Higher and higher rotational speeds are used to achieve high separation rates. A laboratory centrifuge is a centrifuge in which the centrifuge rotor advantageously operates at least 3,000 revolutions per minute, preferably at least 10,000 revolutions per minute, in particular at least 15,000 revolutions per minute, and is usually arranged on a work bench. In order to be able to arrange it on the table, the dimensions of the laboratory centrifuge are in particular smaller than 1m × 1m × 1m, so that the installation space of the laboratory centrifuge is limited. Preferably, the cell depth is limited to a maximum of 70 cm. However, laboratory centrifuges formed as vertical centrifuges are also known; that is, they are between 1m and 1.5m in height so that they can be arranged on the floor of a room.

Such centrifuges are used in the medical, pharmaceutical, biological and chemical fields.

The sample to be centrifuged is stored in a sample container and such a sample container is rotationally driven by means of a centrifuge rotor. In this process, the centrifuge rotor is usually arranged to be rotated by means of a vertical drive shaft driven by an electric motor. The coupling between the centrifuge rotor and the drive shaft is usually performed by means of a hub of the centrifuge rotor.

There are different centrifuge rotors used depending on the application. Thus, the sample container may directly contain the sample, or a separate sample holder containing the sample is inserted into the sample container, so that a large number of samples can be centrifuged simultaneously in one sample container. Conventionally, centrifuge rotors are known in the form of fixed angle rotors, swing-out rotors, and the like.

Regardless of the type of centrifuge rotor, the connection between such a centrifuge rotor and the drive shaft of the centrifuge motor, which ensures locking of the respective centrifuge rotor on the drive shaft during operation of the centrifuge, is largely universal, which makes it possible to use different types of centrifuge rotors in the same centrifuge without any problems.

Such a connection structure is usually formed such that there is a threaded connection between the centrifuge rotor and the shaft, whereby a highly safe and durable connection can be established. A key is required to lock and release the connection; in this way, the threaded connection can be operated. The disadvantages of this connection are: with a key, there are additional elements that may be lost; furthermore, one-handed operation is not possible.

However, the use of automatic locks allowing one-handed operation is also known today. For example, the system is composed of a network located in the ander Unteren

50,37520 Sigma Laborzentrifugen GmbH of Osterode am Harz to

The name of (1) is sold. However, this system has the disadvantage that the centrifugal forces acting on the eccentric element are complicatedly redirected to the coupling element, which can be very error-prone in locking and unlocking, eventually making the operation of such coupling devices unsafe in everyday use.

Disclosure of Invention

It is therefore an object of the present invention to at least partly overcome these disadvantages. Preferably, one-handed operation without the need for additional tools is made possible. In particular, the connection structure will be constructed in such a way that locking is always ensured, whereby no jamming or blocking of the locking element occurs.

This object is achieved by a connection according to claim 1. Advantageous further developments are indicated in the dependent claims and in the following description in conjunction with the drawings.

In the case of the present invention, the actuating device is preferably arranged to be released by the actuating device, and the actuating device is preferably arranged to be released by the actuating device, in such a way that the actuating device is released by the actuating device.

The connection between the centrifuge rotor and the drive shaft of the centrifuge motor running along the axis according to the invention, wherein a first locking element is provided on one of the elements of the centrifuge rotor and the drive shaft and a second locking element is provided on the other of the elements of the centrifuge rotor and the drive shaft, wherein the first locking element is engaged with the second locking element in the connected locked state and disengaged from the second locking element in the unlocked state, is characterized in that an actuation device is present on one of the elements of the centrifuge rotor and the drive shaft, the actuation of which causes the first locking element to be disengaged from the second locking element, whereby the centrifuge rotor can be removed from the drive shaft.

In an advantageous further development, it is proposed that the first locking element is a lever. This makes the locking particularly easy to manage. The connecting structure can be formed particularly thin if the lever arm of the lever can be moved in a plane parallel to the axis. This is particularly the case if the lever arm is able to move in a plane including the axis. In this context, the "lever arm" refers to the part of the lever that comes into a locked state with the second locking element.

In an advantageous further development, it is proposed that the lever is mounted such that it can pivot about an axis. This makes the lever function particularly easy to implement.

In an advantageous further embodiment, it is provided that the lever has an actuating arm arranged opposite the lever arm, wherein the shaft is preferably arranged between the lever arm and the actuating arm. The lock is then particularly easy to handle.

In an advantageous further development, it is provided that the outer point of the actuating arm is at a distance from the axis which is greater than or equal to the distance of the locking point of the lever arm from the axis. The "locking point" is in this case the point at which the first locking element rests on the second locking element in the locked state. This design allows a particularly safe release of the locking, since there is a lever ratio of at least 1 between the actuating arm and the lever arm.

In a further advantageous embodiment, it is provided that the first locking element is formed such that it engages with the second locking element under the influence of centrifugal force. Thus, locking occurs automatically during operation of the centrifuge. Preferably, the center of mass of the first locking element is located in the actuating lever and in particular behind the shaft with respect to the axis, so that the self-locking caused by centrifugal forces is achieved with a particularly simple design.

Alternatively or additionally, it is proposed that the first locking element is preloaded in the direction of engagement with the second locking element. This allows the locking to take place already in the absence of centrifugal force, i.e. automatically, irrespective of the operating state of the centrifuge. At the same time, the preload may also be used as a preload for the actuating means, wherein, however, a separate preload is preferably provided for the actuating means. If a preload is used in addition to the centrifugal force, the locking is enhanced by the centrifugal force due to the rotation of the centrifuge rotor.

In an advantageous further development, it is proposed that the actuating device has a contact surface for a counter-contact surface of the first locking element, wherein one of the two surfaces, the contact surface and the counter-contact surface, has an inclined course in the actuating direction of the actuating device, at least in the locked state of the connecting structure, so that actuation of the actuating device causes the first locking element to pivot. This makes unlocking particularly easy to achieve.

In an advantageous further development, it is proposed that the contact surface extends in an inclined manner in the axial direction of the axis. This makes it very easy to unlock the pivotable lever, for example. The counter contact surface is then preferably straight in the direction of the axis but may also have a slope, which however has to be dimensioned such that an unlocking force is exerted on the first locking element when the actuating device is displaced in the actuating direction.

In an advantageous further development, it is provided that the contact surfaces have a slope in the range from 20 ° to 70 °, preferably in the range from 30 ° to 60 °, in particular in the range from 35 ° to 55 °, preferably 45 °, relative to the axis W, since this enables a large force transmission with a short actuation stroke of the actuating device 146.

In a further advantageous embodiment, it is provided that the contact surface 154 extends in a manner facing the axis W, since the connection structure can thus be kept highly compact.

In an advantageous further development, it is provided that the actuating device is formed sleeve-like at least in certain regions, wherein the contact surface is preferably arranged on an inner side of the actuating device. For example, each cylindrical section may be present in the circumferential direction as a strip in the axial direction, or the sleeve shape may be present only within a certain axial range and abut in a hemispherical or the like shape.

In an advantageous further development, it is proposed that the actuating device can be actuated along an actuation path, wherein the contact surfaces are formed such that the counter-contact surfaces abut against the contact surfaces in the entire actuation path. This enables a very safe unlocking and avoids malfunctions.

In an advantageous further development, it is proposed that the actuating device is formed as a push button which is preloaded against the actuating direction. This makes unlocking particularly easy and ergonomic.

In an advantageous further development, it is proposed that the first locking element is arranged on the centrifuge rotor. This allows the necessary elements to be arranged in the centrifuge rotor, preferably in the hub of the centrifuge rotor, which improves the durability, in particular because the drive shaft itself does not have to have moving parts for the connecting structure.

In an advantageous further development, it is provided that the second locking element is a projection of the drive shaft, behind which the first locking element engages in the locked state. The connection structure is therefore particularly simple to construct.

In an advantageous further development, it is proposed that the actuating device is present on the centrifuge rotor. Thereby, the drive shaft can be designed compact. Alternatively, however, the actuating means may also be present on the drive shaft.

In an advantageous further development, it is provided that at least two first locking elements, preferably three first locking elements, are provided. This makes the locking particularly secure.

In an advantageous further development, it is proposed that the connection structure provides a snap connection, wherein the locking takes place in a frame designed as a releasable catch connection. This makes the locking mechanism particularly secure and the user can hear the locking mechanism snapping into place, making it very easy to verify the security provided. Preferably, in order to provide a snap connection, the first connection element will be preloaded in a direction of engagement with the second locking element. On the other hand, the center of gravity of the first locking element may be arranged such that the engagement occurs automatically when the centrifuge rotor is arranged on the drive shaft.

In an advantageous further development, it is provided that the first connecting device has at least one chamfer serving as a locking aid, wherein the chamfer is preferably parallel to the longitudinal extension of the lever. This makes the connection particularly easy to lock, since it means that the first locking means does not present an obstacle when the centrifuge rotor is fitted to the drive shaft.

Drawings

The features and further advantages of the invention will become apparent from the following description of preferred exemplary embodiments, taken in conjunction with the accompanying drawings. The following is therefore only schematically shown:

figure 1 is a cross-sectional view of a connection according to the invention in a preferred embodiment in an unlocked and separated state,

figure 2 is a cross-sectional view of the connection according to figure 1 in a locked state,

figure 3 is a sectional view of the connection according to figure 1 in the unlocked state,

figure 4 is a cross-sectional perspective view of a hub of a centrifuge rotor according to the connection structure of figure 1,

figure 5 is a perspective view of a drive shaft of a centrifuge rotor according to the coupling structure of figure 1,

FIG. 6 is a detailed cross-sectional view of the connection according to FIG. 1; and

fig. 7 is a laboratory centrifuge with a connection according to the invention according to fig. 1.

Detailed Description

In fig. 1 to 6, a connection structure 100 according to the invention is shown in various views in a preferred embodiment.

It can be seen that the connection 100 between the centrifuge rotor 102 (only partially shown) and the drive shaft 104 (only partially shown) of the centrifuge motor (not further shown) has three levers 106 as first locking elements 106, each lever 106 of the three levers 106 being pivotably mounted about an axis 108.

Such a shaft 108 is arranged in a hub 110 of the centrifuge rotor 102 such that the levers 106 each extend concentrically around a receiving space 112 for the drive shaft 104 at an angular distance of 120 °.

Each of the levers 106 has a lever arm 114 and an actuating arm 116, the actuating arm 116 being arranged opposite the shaft 108, wherein a hook 118 facing the axis W is arranged on the lever arm 114.

The receiving space 112 for the drive shaft 104 has an integrated inner hexagonal portion 120, the inner hexagonal portion 120 corresponding to a respective outer hexagonal portion 122 of the drive shaft 104 and serving to transmit torque. Advantageously, such inner hex portion 120 is made of a harder material than hub 110 and is fixed in the hub 110, e.g., screwed or retracted into hub 110.

The transmission of torque from the drive shaft 104 to the centrifuge rotor 102 thus takes place via the positive-locking

connections

120, 122. As an alternative to the shown hexagonal design, another polygonal design (for example an octagonal design) is also possible, or the positive-locking connection can be realized by a tongue-and-groove connection or a drive pin-and-groove connection or another positive-locking connection allowing torque transmission.

Further, the hub 110 includes an inner taper 124, the inner taper 124 corresponding to a tapered section 126 of the drive shaft 104 and serving to provide a perfect alignment fit as well as a friction fit of the centrifuge rotor 102 on the drive shaft 104. The inner cone 124 merges into an inner cone 128, the inner cone 128 being formed by a bearing block 130 bolted to the hub 110 129, there being a cantilever 131 on the bearing block 130, the shaft 108 being arranged on this cantilever 131. On this bearing block 130 there may also be present preloading means, for example in the form of a spring (not shown), which effect a preloading of the lever arm 114 with the hook 118 towards the axis W. However, in the exemplary embodiment shown, no such separate preloading device is provided.

The drive shaft 104 has a recess 132 with an upper projection 134 above the conical section 126, wherein a chamfer 136 extends above the upper projection 134. Such a projection 134 forms a second locking element.

It can also be seen that the groove 132 has a circumferential configuration in the form of an outer hex 137, the outer hex 137 being oriented parallel to the outer hex 122. Thus, each hook 118 is always parallel to the associated surface of outer hex 137.

The hook 118 has a chamfered surface 138 oriented in the direction of the internal taper 124. In the locked state, the hook 118 engages in the groove 132 and at the same time behind the upper projection 134.

Furthermore, the hub 110 has, above the bearing block 130, a cylindrical cavity 140, which cylindrical cavity 140 is delimited at the top by a cap-like closure element 142. For example, there is an opening 144 in the closure element 142 which can be screwed 143 into the hub 110, the actuating element 146 being accommodated in a slidably displaceable manner in this opening 144.

The actuating element 146 is formed sleeve-like at least in some regions and has a body 148 formed as a push button 148, the body 148 having, in its lower section, a collar 150, which collar 150 projects radially outward and rests on the closing element 142 in the unstressed state of the actuating element 146.

Below the collar 150, a projection 152 is provided, wherein at the transition between the body 148 and the projection 152 opposite the collar 150, there is a section 154 with a conical inner contour, which section 154 serves as a contact surface corresponding to a counterpart contact surface 156 of the lever 106. The contact surface 154 points in the direction of the axis W, which allows the connection to be kept very compact.

The bearing block 130 has a boss 158 passing over the cantilever 131 to form a recess 160 (see fig. 2). A helical spring 162 is arranged on the one hand in such a recess 160 and on the other hand between the projection 152 and the outer circumference of the cavity 140 and preloads the actuating element 146 in an upward direction, i.e. against the actuating direction B of the actuating element 146. The coil spring 162 thereby provides automatic return of the actuating element 146 from the actuated state to the unactuated state.

The actuating element 146 may be displaced along an actuation path, i.e. the actuating element 146 is displaced in an actuation direction B from an unactuated state shown in fig. 2 to a fully downwardly moved state shown in fig. 3.

As can also be seen in fig. 3, the bore 144 has a section 164 with a conical slope, which section 164 corresponds to a conical mating portion 166 of the actuating element 146. As a result, tilting of the actuating element 146 when it is moved by the helical spring 162 against the actuating direction B is effectively prevented.

The connection 100 now operates as follows:

in the state shown in fig. 1, the centrifuge rotor 102 is arranged with its hub 110 on the drive shaft 104 of the centrifuge motor. In the process, the hook 118 is brought by its chamfered face 138 into contact with the chamfered face 136 of the drive shaft 104, causing the lever arm 114 to deflect outwardly relative to the axis W until the hook 118 engages in the groove 132 and thus behind the upper projection 134 (see fig. 2). Thus, the two chamfered

surfaces

136, 138 now provide a locking aid by preventing the hook 118 from catching or hooking the drive shaft 104.

To engage prior to operation of the centrifuge rotor 102, the center of mass M of the lever 106 is located in the actuation arm 116, particularly in the actuation arm 116 outwardly and upwardly relative to the shaft 108, such that gravity causes engagement of the hook 118 in the groove 132.

The initial position of the lever 106 is defined by the tapered inner surface 154 of the actuating element 146. This prevents the actuation arm 116 from tilting outward and coming into contact with the centrifuge rotor 102 downward. The inward inclination is also not a problem, since the drive shaft 104 pushes such a lever 106 back to the correct position when the centrifuge rotor 102 is arranged on top. However, inward tilting may also be prevented by corresponding contact points in the bearing block 130 (not shown).

During operation of the centrifuge rotor 102, the center of mass of the lever 106 disposed above the shaft 108 moves the actuating arm 116 outward, thereby pressing the hook 118 firmly into the groove 132, providing a secure lock. Thus, there is only one displacement element 106, making the locking function less prone to error.

In order to release the locking, the button 148 has to be displaced in the actuation direction B, i.e. downwards. This brings the contact surface 154 into contact with a counter contact surface 156 which is parallel to the axis W in the non-pivoted state.

When the button 148 is further depressed in the actuation direction B, the mating contact surface 156 slides against the contact surface 154, thereby exerting a force on the actuation arm 116, whereby the hook 118 is displaced radially outward until it is completely removed from the groove 132 (see fig. 3).

As a result, the hook 118 no longer rests on the upper projection 134 and the hub 110 can be pulled away from the drive shaft 104, wherein the button 148 slides upwards after being released by the helical spring 162 until the collar 150 rests on the closure element 142 (see fig. 1).

Since the counter contact surface 156 is in contact with the contact surface 146 throughout the entire actuation path of the actuation device 146, a very secure unlocking takes place. Unlocking will also occur in a highly safe and trouble-free manner, since the outer point 168 of the actuation arm 116 is at a distance from the shaft 108 that is greater than or equal to the distance of the locking point 170 of the lever arm 114 from the shaft 108 (see fig. 6); at this point, large lever forces may thus be transferred to the lever arm 114. This is further benefited by the fact that: the contact surface 154 has a slope α in the range of 35 ° to 55 ° relative to the axis W, whereby a large force transmission is possible with a short actuation stroke of the actuation device 146.

Although the example using the lever 106 that pivots about the shaft 108 has been shown above, the lever 106 that pivots about the shaft and is provided on the drive shaft may also be used.

Furthermore, the actuating element 146 does not necessarily have to be provided on the hub 110 of the centrifuge rotor 102; it may also be mounted on the drive shaft.

Fig. 7 shows a laboratory centrifuge 200 equipped with a connection structure 10 according to the invention.

It can be seen that such a laboratory centrifuge 200 is formed in the usual manner and therefore has a housing 202 and a lid 208 for closing a centrifuge container 210, at the front side 204 of the housing 202 a control panel 206 being provided. The fixed angle rotor 12 is disposed in the centrifuge vessel 210 as a centrifuge rotor that may be driven by a drive shaft of a centrifuge motor (neither shown).

As has become apparent from the foregoing description, the present invention provides a connection structure 100 between a drive shaft 104 and a centrifuge rotor 102 of a laboratory centrifuge 200, which connection structure 100 allows for one-handed operation without the need for any additional tools. In this regard, the connection structure 100 is configured such that a locked

state

118, 132, 134 is always ensured, wherein the locking

elements

118, 132, 134 do not jam or block.

All features of the invention may be freely combined, unless otherwise specified. In addition, unless otherwise specified, the features described in the description of the drawings may be freely combined with other features that are features of the present invention. It is not expressly intended that individual features of an example embodiment are limited to combinations with other features of example embodiments. Furthermore, features of the subject matter may be re-formulated as method features and method features may be re-formulated as features of the subject matter. Such reformulations are therefore automatically disclosed.

List of reference numerals

100 in a preferred embodiment, a connection according to the invention

102 centrifuge rotor

104 drive shaft

106 lever, first locking element

108 shaft of lever 106

110 hub

112 receiving space of driving shaft

114 lever arm

116 actuator arm

118 hook

120 hub 110 hexagonal socket

122 outer hexagonal part of the drive shaft 104

124 inner taper of hub 110

126 drive the conical section of the shaft 104

Inner cylindrical portion of 128-hub 110

129 screw support 130 to hub 110

130 supporting seat

131 cantilever for shaft 108 on bearing block 130

132 groove

134 upper projection of groove 132, second locking element

136 drive shaft 104

137 circumferential configuration of the recess 132 in the form of an external hex

138 chamfer on hook 118

140 cylindrical cavity of hub

142 cap-shaped closure element

143 to screw the closure element 142 to the hub 110

144 opening a hole

146 actuating element

148 button, body of actuating element 146

150 ring

152 projection

154 segment with conical inner contour, contact surface

156 mating contact surfaces of the lever 106 on the actuation arm 116

158 bearing block 130 boss

160 concave part

162 helical spring

164 portion of opening 144 with a tapered ramp

166 conical counterpart section of the actuating element 146

168 drive the outer point 116 of the arm

170 locking point of lever arm 114

200 laboratory centrifuge

202 casing

204 housing 202 at the front side

206 control panel

208 cover

210 centrifuge vessel

The slope of the alpha contact surface 154 relative to the axis W

B direction of actuation of the actuating element 146

Center of mass of M lever 106

Axis of W

Claims

1. Connection (100) between a centrifuge rotor (102) and a drive shaft (104) of a centrifuge motor extending along an axis (W), wherein a first locking element (106) is provided on one of the elements of the centrifuge rotor (102) and the drive shaft (104) and a second locking element (134) is provided on the other of the elements of the centrifuge rotor (102) and the drive shaft (104), wherein the first locking element (106) is engaged with the second locking element (134) in a connected, locked state and disengaged from the second locking element (134) in an unlocked state, characterized in that an actuating device (146) is provided on one of the elements of the centrifuge rotor (102) and the drive shaft (104), actuation of the actuating device (146) causing the first locking element (106) to be disengaged from the second locking element (134), whereby the centrifuge rotor (102) is removable from the drive shaft (104).

2. The connection arrangement (100) according to claim 1, characterized in that the first locking element is a lever (106), a lever arm (114) of the lever (106) preferably being movable in a plane parallel to the axis (W), wherein the lever arm (114) in particular is movable in a plane comprising the axis (W).

3. The connection structure (100) according to claim 2, wherein the lever (106) is pivotally mounted about an axis (108).

4. The connection arrangement (100) according to claim 2 or 3, characterized in that the lever (106) has an actuating arm (166) arranged opposite the lever arm (114), wherein the shaft (108) is preferably arranged between the lever arm (114) and the actuating arm (116).

5. The connection arrangement (100) according to any one of claims 2 to 4, characterized in that an outer point of the actuation arm (116) is at a distance from the shaft (108) that is greater than or equal to a distance of a locking point of the lever arm (114) from the shaft (108).

6. The connection arrangement (100) according to any one of the preceding claims, characterised in that the first locking element (106) is formed such that it engages with the second locking element (134) under the influence of centrifugal force, wherein preferably the centre of mass of the first locking element (106) is located in the actuating arm (114) according to claim 4 or 5 and in particular behind the shaft (108) with respect to the axis (W).

7. The connection arrangement (100) according to any one of the preceding claims, characterised in that the actuating device (146) has a contact surface (154) for a counter-contact surface (156) of the first locking element (106), wherein one of the two surfaces, contact surface (154) and counter-contact surface, has an inclined course in an actuating direction (B) of the actuating device (146) at least in the locked state of the connection arrangement (100), such that actuation of the actuating device (146) causes the first locking element (106) to pivot, wherein the contact surface (154) preferably extends inclined in the axial direction of the axis (W) and/or pointing towards the axis (W).

8. The connection structure (100) according to claim 7, characterized in that the contact surface (154) has a slope (a) in the range of 20 ° to 70 °, preferably in the range of 30 ° to 60 °, in particular in the range of 35 ° to 55 °, advantageously 45 °, with respect to the axis (W).

9. The connection arrangement (100) according to any one of the preceding claims, characterised in that the actuating device (146) is formed sleeve-like at least in certain regions, wherein the contact surface (154) according to claim 7 or 8 is preferably provided on an inner side of the actuating device (146).

10. The connection arrangement (100) according to any one of claims 7 to 9, characterised in that the actuating device (146) is actuatable along an actuating path, wherein the contact surface (146) is formed such that the counter contact surface (156) abuts against the contact surface throughout the drive path.

11. The connection structure (100) according to any one of the preceding claims, wherein the actuation means (146) is formed as a button (148) preloaded (162) against the actuation direction (B).

12. The connection structure (100) according to any one of the preceding claims, wherein the first locking element (106) is provided on the centrifuge rotor (102).

13. The connection arrangement (100) according to any one of the preceding claims, characterised in that the second locking element (134) is a projection (134) of the drive shaft (104), the first locking element (106) engaging behind the projection (134) in the locked state.

14. The connection structure (100) according to any one of the preceding claims, wherein the actuation device (146) is present on the centrifuge rotor (102).

15. The connection according to any one of the preceding claims, characterized in that the connection provides a snap connection, wherein the locking takes place within a frame designed as a releasable, catch connection.

16. The connection structure (100) according to any one of the preceding claims, wherein there are at least two first locking elements (106), preferably three first locking elements (106).

17. The connection according to any one of the preceding claims, wherein the first locking element is preloaded in a direction of engagement with the second locking element.

18. The connection arrangement (100) according to any one of the preceding claims, characterised in that the first connection device (106) has at least one chamfer (138) serving as a locking aid, wherein the chamfer (138) is preferably parallel to the longitudinal extension of the lever (106).